The treatment of waste water is a significant problem, especially for residential developments which are not connected to community sewer systems. In these situations, waste water is conventionally treated by introducing it into a septic tank where it is initially treated. Outflow from the septic tank is then distributed among lateral fields maintained in the ground. The effectiveness of a septic system depends on many factors including the size of the lot on which the residence is located, the amount of waste water that is introduced into the system on a daily basis and the quality of the soil in which the lateral fields of the septic system are placed. Even if a residential septic system is effective in treating effluents, it sometimes contaminates ground water.
One of the newer methods for treating waste water is the constructed wetland system as discussed, for example, in U.S. Pat. No. 5,174,897. In this system, the effluent flows into a sediment basin (2) and then into a level lip spreader (3) which is designed to spread the flow uniformly across a primary grass filter (4). One difficulty encountered with this type of constructed wetland system is that effluent introduced into the system is not uniformly distributed throughout the system, but rather is input into the system only into a narrow section of the system, i.e., the level lip spreader (3).
Another system for the treatment of municipal waste water located below ground is disclosed by U.S. Pat. No. 5,156,741. This large system utilizes a recirculation system tied to turf grass to recirculate the treated water back into the system after initial treatment via a municipal treatment plant. This system also discloses a series of pipes used for the disbursement of the waste water through the ground for treatment, as shown in FIG. 1. This system requires a generally dry portion of ground to be present above the operative portion of the system used for the treatment of the waste water.
Another apparatus for treating household effluent is disclosed in U.S. Pat. No. 4,824,572. In this system, effluent flows from a septic tank or a series of septic tanks into a treatment bed. The treatment bed includes several layers of gravel and a layer of topsoil into which reeds are planted for treating the effluent. A perforated header pipe distributes the incoming effluent across the head of the bed.
Other systems for the treatment of waste water using microorganisms and plants are disclosed, for example, in U.S. Pat. Nos. 4,415,450, 3,770,623, 5,073,257, 4,995,969 and 4,333,837.
In addition, a system for the treatment of storm water runoff is disclosed in U.S. Pat. Nos. 5,549,817 and 5,437,786.
Constructed wetland systems have begun to be utilized for the treatment of effluent, particularly household effluent. Many of these wetland systems currently in use still have significant deficiencies, including an inability to uniformly distribute the effluent throughout the wetland system, a difficulty in retaining the effluent in the wetland system for a sufficient period of time to adequately treat and filter the effluent, complications and expenses associated with the installation of conventional constructed wetland systems, and difficulty in maintenance and monitoring of conventional constructed wetland cells so that they will adequately treat and filter effluent introduced into these systems. The design of the invention disclosed within this specification addresses these problems.
Accordingly, it is an aspect of this invention to disclose an improved waste water treatment system.
It is a further aspect of this invention to disclose an improved waste water treatment system which is easy to install and maintain.
It is a further aspect of this invention to disclose a waste water treatment system that can be utilized with a conventional residential septic system.
It is a further aspect of this invention to disclose a waste water treatment system wherein the effluent is uniformly distributed throughout the system for efficient treatment.
It is a still further aspect of this invention to disclose a waste water treatment system utilizing a constructed wetland cell, wherein the effluent introduced within the constructed wetland cell is retained within that cell for a sufficient period of time to adequately treat the effluent.
It is a still further aspect of this invention to disclose a waste water treatment system comprising at least a pair of alternating constructed wetland cells, wherein effluent is introduced into only one of those cells for a sufficient period of time to treat the effluent prior to introducing additional effluent into an alternative cell.
It is a still further aspect of this invention to disclose a waste water treatment system utilizing a dump valve system whereby substantially all of the treated and filtered effluent contained within the system is removed from the system at one time.
It is a still further aspect of this invention to disclose a recirculation system wherein filtered effluent from a waste water treatment system is recirculated back into the waste water treatment system for further treatment prior to final discharge from the waste water treatment system.
It is a still further aspect of this invention to disclose a waste water treatment system utilizing a septic system and a constructed wetland system in combination, wherein the septic tank utilizes a pump to pump predetermined quantities of effluent into the constructed wetland system.
It is a still further aspect of this invention to disclose a waste water treatment system utilizing a septic system and a constructed wetland system in combination wherein the septic system contains a pump and a filter to prefilter the effluent prior to introduction into the constructed wetland system.
It is a still further aspect of this invention to disclose a process for the treatment of waste water utilizing a constructed wetland system.
These and other aspects of the invention can be obtained by the disclosed design of the waste water treatment system for the treatment of effluent and the process for the treatment of effluent utilizing the disclosed waste water treatment system.